Retractable and expandable trailer

ABSTRACT

The trailer comprises a rectangular framework, a loading box fixedly mounted on the framework and including an horizontal platform, and a group of freely rotatable carrying wheels enabling to pull the trailer where the frames are drawn apart from one another and a retracted position where the frames are drawn in towards one another. The framework holds the frames by means of supports, that are arranged to permit a simultaneous transversal and longitudinal movement of the frames with respect to the framework when said frames are moved between a widened position and a drawn in position. The carrying wheels are respectively fixed to the two frames, and an articulation device enables to cause the frames to move by transversal and longitudinal sliding in the supports between the widened position and said drawn in position and vice versa. Longitudinal members are adapted to be juxtaposed relatively to the horizontal platform on both sides of the latter in expanded position of said trailer.

BACKGROUND OF THE INVENTION

[0001] (a) Field of the Invention

[0002] The invention concerns a trailer of the type in which the widthcan vary depending on specific need. More particularly, the invention isdirected to a trailer that is provided with a mechanism which enables tomove away the carrying wheels, while obtaining a loading box that can bewidened in the same proportions.

[0003] (b) Description of the Prior Art

[0004] The use of trailers hitched behind a vehicle often results inproblems of width, specially with respect to small trailers that onewould wish to place behind a small vehicle such as an all-terrainvehicle. Under these circumstances, one must turn to trailers ofdifferent widths, alternatively resort to a trailer that can be adjustedto different widths.

[0005] Structures that permit the expansion and the retraction of atrailer are known such as those described in the following U.S. patents:

[0006] U.S. Pat. No. 4,221,398

[0007] U.S. Pat. No. 4,772,038

[0008] U.S. Pat. No. 5,249,823

[0009] U.S. Pat. No. 5,529,826

[0010] U.S. Pat. No. 5,326,128

[0011] U.S. Pat. No. 5,332,276

[0012] However, these structures are all as much complicated as oneanother and do not permit the construction of a retractable andexpandable trailer at a reasonable cost that is also easy to operate.

SUMMARY OF THE INVENTION

[0013] It is an object of the invention to provide a trailer whose widthcan be modified if needed, that is not costly and is easy to adjust.

[0014] It is also an object of the invention to provide a mechanismwhich is simple, reliable and not costly permitting to modify the widthof a trailer.

[0015] The present invention concerns a retractable and expandabletrailer comprising a rectangular framework, a loading box fixed to theframework and including an horizontal freely rotatable carrying wheelsenabling to pull the trailer. The latter is characterized in that thereare provided two frames disposed under the framework and arranged toengaged into one another between an expanded position of the trailerwhere the frames are drawn apart from one another and a retractedposition of the trailer where the frames are drawn nearer to oneanother, supports fixedly mounted on the framework, the frameworkholding the frames by means of the supports, the supports being arrangedto permit a simultaneous transversal and longitudinal movement of theframes with respect to the framework when the frames are moved from anexpanded position to a retracted position, the carrying wheels beingrespectively fixed to the two frames, and an articulation devicepermitting to move the frames by transversal and longitudinal sliding inthe supports from an expanded position to a retracted position and viceversa, and longitudinal members adapted to juxtaposed the horizontalplatform on both sides of the latter in expanded position of thetrailer.

[0016] According to a preferred embodiment of the invention, each frameincludes a base and two legs that are perpendicular to the base, eachleg being inserted in at least one of the supports in which they can besubjected to the transversal and longitudinal movements, verticallateral panels each rising from a base of a corresponding frame andfixed to the base in order to define the two sides of the loading box.

[0017] Preferably, the trailer comprises a front panel rising from thefront end of the rectangular framework, to join the vertical lateralpanels and thereby constitute the loading box.

[0018] The rectangular framework preferably includes lateral sides; arear side and a front side and a central link, fixed between the rearand front sides; the longitudinal members are each pivotally mountedalong the lateral sides of the rectangular framework to adopt either avertical position in retracted position of the trailer, where thelongitudinal members and the panels abut one another; or, a horizontalposition in expanded position of the trailer where the longitudinalmembers then constitute extension of the platform.

[0019] According to a preferred embodiment of the invention, eachlongitudinal member comprises a secondary panel perpendicularly fixed atone end of the longitudinal member thus constituting an extension of thefront panel in expanded position of the trailer when the longitudinalmember is in horizontal position; when the member is in verticalposition, in the retracted position of the trailer, the secondary panelis positioned outside the front panel and against the latter, while eachlateral panel rests on a corresponding longitudinal member, the latterthen being in vertical position.

[0020] According to another preferred embodiment of the invention, thearticulation device comprises a pivoting rod, that is articulated at oneend along a leg of a frame and at the other end along a correspondingleg of the other frame, the pivoting rod being mounted on the framework,and enabling a 180° rotation of the rod causing a drawing in or drawingout of the frames between in the retracted and expanded positions, byarticulation of the rotary rod with respect to the two legs on which itis articulated.

[0021] Preferably, the articulation device comprises two articulatedrods, so that each leg of a frame is connected to a corresponding leg ofthe other frame.

[0022] According to another preferred embodiment of the invention, thetrailer comprises a pivot pulley fixed to each of the articulated rods,at a location where the latter pivots on the framework, driving meansprovided for rotation of the two pulleys and thus causing a 180°rotation of each of the articulated rods, and consequently, drawing outor in of the two frames.

[0023] Each of the pivoting rod is preferably pivotally mounted on thecentral link of the framework.

[0024] According to another preferred embodiment of the invention, thetrailer comprises a drawbar that is mounted on the framework, atransmission mounted on the drawbar, the transmission being operativelyconnected to each of the articulated rods, by means of the pivotpulleys.

[0025] Preferably, the trailer according to the invention comprises asupport for each of the two legs of the two frames, the supports beingshaped to define a rectangular opening capable of receiving one of thelegs and permitting a transversal and longitudinal sliding of the legsin the supports.

[0026] According to another preferred embodiment of the invention, thetransmission comprises a driving pulley as well as a crank in order torotate the driving pulley. The pivot pulley and the driving pulley arepreferably sheave wheels which are functionally connected to one anotherby means of a system of straps.

BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The invention will be better understood with reference to apreferred embodiment given by way of example and without limitation ofthe scope of the invention, said preferred embodiment being illustratedby means of the annexed drawings, in which

[0028]FIG. 1 is a perspective view taken from underneath a traileraccording to the invention, illustrating the mechanism permitting thewidening and narrowing of the trailer;

[0029]FIG. 2 is a perspective view showing the trailer in expandedposition;

[0030]FIG. 3 is a schematic view in perspective illustrating alongitudinal pivoting member used to complete the platform when thetrailer is in expanded position;

[0031]FIG. 4 is a schematic cross-section view showing the longitudinalmember in a horizontal position to complete the platform when thetrailer is in expanded position;

[0032]FIG. 5 is another schematic view illustrating the longitudinalmember while being raised by pivoting when the trailer adopts aretracted position;

[0033]FIG. 6 is a schematic section view showing the longitudinal memberin contact with the lateral wall of the loading box, when the trailer isin expanded position;

[0034]FIG. 7 is a schematic view illustrating the mechanism used towiden the trailer, in retracted position;

[0035]FIG. 8 is a view similar to FIG. 7, in an initial intermediatewidened position;

[0036]FIG. 9 is a view similar to FIG. 7, in an advanced intermediatewidened position; and

[0037]FIG. 10 is a view similar to FIG. 7, in a final widened position.

DESCRIPTION OF THE PREFERRED EMBODIMENT

[0038] With reference to the drawings, it will be seen that a traileraccording to the invention first consists of a framework 1 that isgenerally rectangular, and carries two movable frames 3 and 5, on whichcarrying wheels 7 and 9 are mounted, by means of freely rotatablecylinders, respectively 11 and 13, held to the frames by means ofsuitable supports 15 and 17.

[0039] More specifically, rectangular framework 1 includes lateral sides19, 21, a front side 23, a rear side 25 as well as a central link 27that is fixedly mounted in known matter such as by welding, betweenfront and rear sides 23, 25 as well illustrated in the drawingsparticularly FIG. 1. To draw the trailer, there is provided a drawbar 29that is fixedly mounted on front side 23 of rectangular framework 1,said drawbar thereby constituting a continuity of central link 27, asillustrated. Finally, the rectangular framework comprises four supports31, 33, 35 and 37 in the shape of a rectangular U shaped members whosespecific shape and characteristics will be described in detail hereinbellow.

[0040] One of the essential characteristics of the invention is thepresence of two movable frames 3 and 5 which will now detailed. The twoframes 3, 5 being identical, only one will be described in details, i.e.frame 3. Frame 3 generally appears as a U shaped member, including abase 39 and two legs 41 and 43 which are parallel with one another andperpendicular to base 39. To give a satisfactory stiffness to frame 3,there is provided an oblique member 45, connecting base 33 to leg 41.Frame 5 being identical to frame 3, it will be sufficient to identifyits corresponding components by means of reference numerals. It willtherefore be seen that frame 5 includes legs 47, 49, base 51 and aoblique reinforcement member 53.

[0041] As described above, carrying wheels 7 and 9 are fixedly mountedon the two frames 3 and 5, i.e. by means of supports 15 and 17 andfreely rotatable cylinders 11 and 13. As seen in the drawings, support15 is mounted on a plate 54, that is welded to frame 3 at the level ofbase 39 and oblique member 45. Similarly, support 17 is mounted on aplate 56 that is welded to frame 5 on base 51 and oblique member 53. Itwill be noted here that the trailer includes a loading box 87 primarilymade of a horizontal platform 89, fixed in known manner to framework 1,and vertical lateral panels 91, 93, preferably fixedly mounted on bases39 and 51 respectively of frames 3 and 5. To complete loading box 87,there are provided vertical front and rear panels 95 and 97 that arefixedly mounted in known manner to front and rear sides 23 and 25 of theframework. The pieces used to complete the loading box when the traileris in widened position will be discussed later.

[0042] Obviously, in order that the two frames 3, 5 be operative, thelatters must be held to framework 1 and underneath the latter. Toachieve this, it should be understood that the two frames are connectedtogether by means of an arrangement which will be discussed later andwhich is arranged so that the two frames constitute one single assembly.To hold the latter, there is provided a group of four U shaped supportunits 31, 33, 35 and 37, as mentioned above which are all identical toone another and are fixedly mounted in a rigid manner to framework 1.More specifically, each U shaped support unit comprises two downwardlydirected vertical tongues 55, 57 which are fixed such as by welding orin any other manner to framework 1, on the lateral sides 19, 21 of thelatter, as illustrated in the drawings. The base of each U-shaped unit,on the other hand, consists of a metallic rod 59 that is parallel to thecorresponding lateral sides 19, 21, and that connects vertical tongues65, 67 so as to provide a rectangular space 61 whose dimension are suchthat a leg 41, 43, 47 or 49 can longitudinally and transversally slidetherein in the direction indicated by arrows 63 and 65.

[0043] We will explain later that the two frames 3 and 5 are movablewith respect to one another by widening or drawing in, following andarticulation caused by a mechanism that will be description herein.Rectangular spaces 61 have been provided at the level of the U-shapedunits 31, 33, 35 and 37 to provide for this relative movement of the twoframes.

[0044] The articulation, enabling the two frames to widen or to retract,depending on specific needs will now be described. It will first be seenthat the two frames 3, 5 are arranged to penetrate one another at thelevel of their legs 41, 47 and 43, 49 and that these are adjacent bypairs i.e. pair 41, 47 and pair 43, 49. To achieve this, there isprovided an articulation mechanism characterized in that at the meetingpoint between each pairs of legs 41, 47 and 43, 49 there is provided apivoting rod 67 that is pivotally mounted on central link 27, in thecentral portion thereof, at 68. It will be noted that to simplify thedescription, the two pivoting rods are identified by the same referencenumeral, such as 67.

[0045] To still simplify the description, we will restrict thedescription to pivoting rod 67 which connects legs 41 and 47, it beingunderstood that the other pivoting rod 67 which connects legs 43 and 49is identical and mounted in the same manner between legs 43, 49.

[0046] Underneath the surface of legs 41, 47, at a point located at ashort distance of the free end of each of the two legs, there arefixedly mounted, such as by welding or any other manner known to oneskilled in the art, connections in the form of short bands 69, 71.Pivoting rod 67, on the other hand, is fixed at its two ends to bands69, 71, by means of pivot joints 73, 75. The possibility of allowingpivoting rod 67 to rotate up to 180° at 68, in one direction or theother and the presence of articulations at 73, 75 enables the two framesto retract or widen between an open position and a closed position asclearly illustrated in FIGS. 7 to 10. This operation will obviouslyproduce a simultaneous longitudinal and transversal movement of legs 41,47 and 43, 49 in rectangular space 61 according to arrows 63 and 65 asmentioned above.

[0047] The articulation about points 73, 75 and the pivoting movementabout point 68 are made possible by means of a combination of pulleys77, 79 and 81 and straps 83 and 84 that will know be described. Pulleys77 and 79 are operatively welded in known manner on pivoting rods 67 asseen in the drawings, these two pulleys 77, 79 being connected togetherby means of driving belt 83. To complete the operation of pulleys 77,79, there is provided a transmission box 85, mounted in known manner ondrawbar 29 and connected also in known manner to a crank shaft 87 andpulley 81. Driving belt 85 connects pulley 81 to pulley 79.

[0048] To widen or draw in movable frames 3 and 5, and consequentlycarrying wheels 7 and 9 and vertical lateral panel 91, 93, it is merelysufficient to use the crank 87 in one direction or the other, therebydriving the two pulleys 77, 79 and causing the two pivoting rods 67 topivot up to 180°. To provide a widening movement, it will be seen thatthe articulation of rod 67 and the longitudinal and transversalmovements of legs 41, 43, 47 and 49 will cause frames 3 and 5 to adopt awidened position. Reversely, during the operation of the crank in theopposite direction, again, but in the opposite direction and alwaysaccording to longitudinal and transversal movements, there will be anarrowing of the two frames, until reaching a retracted position of thetrailer. Reference will made particularly to FIGS. 7 and 10 for andillustration of this operation.

[0049] When the trailer is in widened position, there is obviouslysomething missing at the level of the platform. To overcome thisabsence, there are provided longitudinal members 99, 101 that arepivotally mounted respectively along lateral side 19 and 21 of framework1. With reference to FIG. 4, it will be seen that in vertical position,longitudinal member 99, 101 constitutes one side of the loading box byresting against lateral panel 91. However, in horizontal position, asseen in FIG. 6, the longitudinal member 99, 101 now completes platform89 of the loading box.

[0050] Referring now to FIGS. 3 and 4, it will be seen that eachlongitudinal member 99, 101 comprises a secondary panel 103 that isperpendicularly fixed to one end of the latter to constitute andextension of front panel 95 when the trailer is in expanded position andlongitudinal member 99, 101 is horizontally mounted along platform 89.On the other hand, in a closed position of the trailer, secondary panel103 is folded exteriorly and against front panel 95. A second secondarypanel will be provided, in the case where the loading box also comprisesa rear panel 97.

[0051] It is understood that according to the invention modifications tothe preferred embodiment that has be described are possible, of course,provided that these modifications are within the scope of the appendedclaims.

1. Retractable and expandable trailer comprising a rectangularframework, a loading box fixedly mounted on said framework and includingan horizontal platform, and a group of freely rotatable carrying wheelsenabling to pull said trailer, characterized in that there are providedtwo frames disposed underneath the framework and arranged to be engagedinto one another between an expanded position of said trailer where saidframes are drawn apart from one another and a retracted position of saidtrailer where said frames are drawn in towards one another, supportsfixedly mounted on said framework, said framework holding said frames bymeans of said supports, said supports being arranged to permit asimultaneous transversal and longitudinal movement of said frames withrespect to said framework when said frames are moved between a widenedposition and a drawn in position, said carrying wheels beingrespectively fixed to the two frames, and an articulation deviceenabling to cause said frames to move by transversal and longitudinalsliding in said supports between said widened position and said drawn inposition and vice versa, and longitudinal members adapted to bejuxtaposed relatively to said horizontal platform on both sides of thelatter in expanded position of said trailer.
 2. A trailer according toclaim 1, characterized in that said frames each include a base and twolegs perpendicular to said base, said legs being each introduced in atleast one of said supports in which they can be subjected to saidtransversal and longitudinal movement, vertical lateral panels eachrising from a base of a corresponding frame and fixed to said base inorder to define the two sides of the loading box.
 3. A trailer accordingto claim 2 characterized in that it comprises a front panel rising fromthe front end of said rectangular framework, to join said verticallateral panels and thereby constitute said loading box.
 4. A traileraccording to claim 3 characterized in that said rectangular panelincludes lateral sides, a rear side and a front side as well as acentral link, fixed between the rear and front sides, said longitudinalmembers are each mounted in order to pivot along said lateral sides ofsaid rectangular framework to adopt either a vertical position inretracted position of said trailer where said longitudinal members andsaid panels are placed against one another, or a horizontal position inexpanded position of said trailer, said longitudinal members thenconstituting extension of said platform.
 5. A trailer according to claim4, characterized in that each longitudinal member comprises a secondarypanel perpendicularly fixed at one end of said longitudinal member toconstitute an extension of the front panel in expanded position of saidtrailer, when said longitudinal panel is in horizontal position, andwhen said member is in vertical position in retracted position of saidtrailer, said secondary panel is placed outside said front panel andagainst the latter, while each said lateral panels rests on acorresponding longitudinal member, the latter then being in verticalposition.
 6. A trailer according to claim 2, characterized in that thearticulation device comprises a pivoting rod, that is articulated at oneend along a leg of a frame and at the other end, along a correspondingleg of the other frame, said pivoting rod being pivotally mounted onsaid framework, and means enabling to cause a 180° rotation of said rodand to causing a retraction or expansion of said frames between saiddrawn in and drawn out positions, by articulation of said pivoting rodwith respect to the two legs on which it is articulated.
 7. A traileraccording to claim 6, characterized in that the articulation devicecomprises two pivoting rods, so that each leg of one frame is connectedto a corresponding leg of the other frame.
 8. A trailer according toclaim 7, characterized in that it comprises a pivot pulley fixedlymounted to each rods, at a location where the latter pivots on saidframework, driving means provided for rotation of the two pulleys andthus causing a 180° rotation of each articulated rods, and consequently,extension or retraction of the two frames.
 9. A trailer according toclaim 8, characterized in that each pivoting rod is pivotally mounted onthe central link of said framework.
 10. A trailer according to claim 8,characterized in that it comprises a drawbar that is fixedly mounted onsaid framework, a transmission box mounted on said drawbar, saidtransmission box being operatively connected to each articulated rods bymeans of said pivot pulleys.
 11. A trailer according to claim 1,characterized in that it comprises one said support for each leg of thetwo frames, said supports being shaped to define a rectangular openingcapable of receiving one said leg and enabling a transversal andlongitudinal sliding of said legs in said supports.
 12. A traileraccording to claim 10, characterized in that said transmission boxincludes a driving pulley as well as a crank in order to rotate thedriving pulley.
 13. A trailer according to claim 12, characterized inthat said pivot pulleys and said trailing pulley comprised sheave wheels